Effect of harvesting autogenous laryngeal cartilage for laryngotracheal reconstruction on laryngeal growth and support

Objective: Determine the effect of harvesting autogenous thyroid cartilage on subsequent laryngeal growth and stability in a kitten model. Study Desig n: Prospective controlled trial in animals. Methods: Seventeen kittens were divided into three groups. Group one (n = 5) included kittens that underwe nt a unilateral thyroid cartilage resection, Group two (n = 5) included kit tens that underwent a bilateral cartilage resection. Group three (n = 7) co mprised kittens that did not undergo any surgical procedure (controls), All animals underwent endoscopic examination followed by the surgical procedur e designated for that group. Kittens were then assessed daily for 2.5 month s. At the end of that period the now "adolescent" cats were examined endosc opically then euthanized. The larynx was removed for gross and histopatholo gic analysis. Results: All kittens tolerated the surgical procedure without airway compromise. Subsequent endoscopic examination 2.5 months after surg ery revealed normal vocal cord function. Measurements of the true vocal cor d and aryepiglottic and subglottic diameter did not differ significantly (o ne-way analysis of variance, P = .05) with respect to the side or the group . Histopathologic evaluation of the laryngeal sections indicated a patent a irway, stable and viable thyroid cartilage, and no evidence of cartilaginou s regrowth. Conclusions: The removal of unilateral and bilateral superior t hyroid alar cartilage can be performed in kittens without postoperative res piratory or wound problems. The harvesting of autogenous thyroid cartilage has no apparent effect on subsequent laryngeal growth and stability in a ki tten model. Key Words: Laryngotracheal reconstruction, subglottic stenosis, kitten, human, autogenous laryngeal cartilage graft.